Device for discharging the gases exhaled by the wearer of a respiratory apparatus



J. Y. CO USTEAU ET AL DEVICE FOR DISCHARGING THE GASES EXHALED BY THE WEARER Nov. 25, 1969 3,480,011

OF A RESPIRATORY APPARATUS Filed March 7, '1966 mum/m s JACQUz-sJ VZ: Caz/S7540 fM/Lf GAGA Aw firrye:

United States Patent DEVICE FOR DISCHARGING THE GASES EXHALED BY THE WEARER OF A RESPI- RATORY APPARATUS Jacques Yves Cousteau, Monaco, and Emile Gagnan, Paris, France, assignors to La Spirotechnique Filed Mar. 7, 1966, Ser. No. 532,354 Int. Cl. A62b 7/04, 11/00 US. Cl. 128142.2 4 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a device for discharging the gases exhaled by the wearer of a respiratory apparatus, the said device comprising a closure member actuated by a flexible diaphragm which separates from the ambient medium a chamber in which is established in practice the pressure of the exhaled gases, which diaphragm opens the closure member when the pressure in this chamber is higher than the pressure of the ambient medium, the device being combined with a demand pressure reducing valve, which ensures the supply of respiratory mixture and which comprises on the inlet pipe of this mixture another closure member which is actuated by the said diaphragm and expands the said mixture substantially to the ambient pressure; in the said chamber, there are successively established in practice the pressure of the exhaled gases and the very similar pressure of the mixture after expansion by the said other closure member; the control of the two closure members is such that the direction of displacement of the diaphragm which opens one of these members closes the other.

Such a device is known for the equipment of respiratory apparatus designed to operate under water or in a toxic or radioactive atmosphere. The respiratory mixture inhaled by the wearer is supplied by the expansion arrangement, while the exhaled gases pass into one or more automatic valves and thence into a recovery apparatus, for example, towards an apparatus where the gases are freed from their carbon dioxide and are enriched with oxygen.

The discharge device according to the invention is characterised in that the said closure members are fast with one another, for example, their movable parts are fixed to a single rod, and in that the said members are arranged in such manner that when one is closed, the other is opened. For example, the assembly of the said two closure members comprises essentially a fixed part in the form of a hollow cylinder, of which the two ends or two lateral openings open into the expansion chamber, two distributor pistons actuated by the diaphragm and capable of being displaced in the cylinder and of extending beyond the ends or the said openings of the latter, and a fixed or movable partition which closes the cavity of the cylinder between the pistons, the respiratory mixture to be expanded reaching the cylinder between one of its ends or one of the openings and the partition and the exhaled gases leaving the device by a lateral orifice of the cylinder, which orifice is situated between the other end or the other opening and the partition.

This construction of the device enables it to function with very slight frictional effects, thus making easy the respiration of the wearer.

The accompanying figure is a diagrammatic sectional view of one embodiment of the invention, which is given as a non-limiting example.

The casing of the device comprises a body 2 and a cover 4 in which are formed holes such as 3, 5. Clamped between these two parts is the rim of a flexible diaphragm 6, the center of which is reinforced by two plates 8, 9.

As is known, the mouthpiece 24, which the wearer holds between his teeth, is connected to the expansion chamber 18 of the device by an inhaling pipe 22 and an exhaling pipe 34; automatic valves 38, ensure that the circulation in these pipes is in one direction. The chamber is also in communication with the inhaling and exhaling pipes.

The distribution of the gases is achieved by distributor pistons 52, 54, which are fixed on the same rod 56. The piston 52 is formed by a resilient obturating member, for example, by a ring of ethylene polytetrafiuoride clamped between a recessed nut 58 screwed on the rod and a washer 60; the piston 54 is formed in similar manner. The pistons 52, 54 constitute the movable parts of closure members serving respectively for the supply of respiratory mixture and for the discharge of the exhaled gases.

The rod 56 comprises at its center two collars between which is mounted a toroidal ring 62, which forms a movable partition obstructing the interior of a cylinder 64 fixed to the body of the expansion arrangement.

The assembly of the elements 52, 54, 62 can be displaced with low friction in the cylinder 64 and partially project therefrom. Each of the said elements closes the cylinder in a substantially fluid-tight manner when it is inside the said cylinder. The distance between the immediately adjacent pistons is such that they are both simultaneously in contact with the ends of the cylinder. This assembly constitutes a kind of slide valve distribution.

The cylinder 64 comprises two lateral orifices 66, 68. The orifice 66, opening between the left end of the cylinder and the position farthest to the left of the ring 62, is connected to a tube 16 through which is supplied the respiratory mixture under pressure intended for the wearer. The orifice '68 is symmetrical and is connected to a tube 30 which is arranged to direct the gases exhaled by the wearer towards a recovery apparatus.

The rod 56 is actuated by the diaphragm 6 by means of a lever 70, the said lever pivoting on a pivot pin 71 and terminating in a pin 72 fitted into a groove in the nut 58.

The operation of this device is as follows. In the position illustrated the piston 52 is inside the cylinder 64; it is then closing the passage for the respiratory mixture being supplied through the tube 16 from a supply of the mixture (not shown). The piston 54 has extended slightly beyond the right end 76 of the cylinder; the exhaled gases, arriving through the pipe 34, can thus pass through the orifice 68 towards the tube 30 comprising exhaust means through which they are exhausted; this passage will be even freer when the diaphragm will have pushed the rod 56 further towards the right.

When the wearer has finished exhaling and is inhaling, the diaphragm 6, by means of the lever 70, displaces the rod 56 towards the left. There is then successively obtained the closure of the pasage for the exhaled gases, the piston 54 entering the cylinder, and then immediately afterwards, the opening of the passage for the respiratory mixture, the piston 52 extending from the cylinder. The diaphragm 6, the piston 52, the parts which connect them and the left end of the cylinder 64 constitute a demand expansion or pressure reducing arrangement.

The rod 56 is displaced very easily, because the pressures exerted by the gases are balanced; the respiratory mixture exerts just as strong a thrust towards the left as towards the right, because the ring 62 and the piston 52 are of the same diameter; the same applies as regards the thrust of the exhaled gases, which is exerted on the ring 62 and the piston 54.

The expansion arrangement which has been described may be modified without departing from the scope of the present invention; for example, it is possible to provide, not a movable partition but a partition fixed to the cylinder 64 and through which the rod 56 would pass with slight friction and with a sufficient fluid-tightness. The cylinder 64 could be longer, its cavity then being brought into communication with the expansion chamber 18 by lateral openings, in front of which the pistons 52, 54 would pass.

What we claim is:

1. A demand breathing device having supply means for a respiratory mixture and exhaust means for exhaled gases, comprising means defining a chamber, means for interconnecting the chamber to the respiratory passages of a user, a flexible diaphragm which separates the interior of the chamber from the ambient medium, first connection means for establishing communication between said chamber and said supply means for a respiratory mixture and a first closure member movable between a closed position in which it interrupts said first connection means and an open position in which it establishes said first connection means, second connection means for establishing communication between said chamber and said exhaust means and a second closure member movable between a closed position in which it interrupts said second connection means and an open position in which it establishes said second connection means, means rigidly interconnecting said first and second closure members for movement together as a unit, and means responsive to movement of said diaphragm in a direction to decrease the volume of said chamber to open said first closure member and close said second closure member and responsive to movement of said diaphragm in a direction to increase the volume of said chamber to close said first closure member and open said second closure member, each of said closure members being closed when the other is open.

2. A breathing device as claimed in claim 1, wherein said rigid means comprises a rod interconnecting said first and second closure members.

3. A breathing device as claimed in claim 1, and a hollow cylinder in which said unit is slidably disposed, said hollow cylinder having openings adjacent opposite ends thereof that communicate with said chamber, said closure members being pistons slidable in the cylinder to open and close said end openings, and partition means inside said cylinder between said closure members for permanently interrupting fiuid communication between said supply means and said exhaust means, said first and second connection means opening into said cylinder on opposite sides of said partition means in all positions of said pistons but endwise inwardly of said end openings.

4. A breathing device as claimed in claim 3, said end openings being open opposite ends of said cylinder.

References Cited UNITED STATES PATENTS 2,364,626 12/1944 Emerson 128-l45.7 2,770,232 11/1956 Falk 128145.7

FOREIGN PATENTS 1,103,799 3/1961 Germany.

WILLIAM E. KAMM, Primary Examiner 

